JULV 27, I905J 



NA TURE 



MINERALS, ROCKS, FOSSILS. 



A larce ^tock of BRITISH AND FOREIGN MINERALS always on vie» 



A SPECIALI ly. 

 Special display for Teachers and Students on Saturdays. Open till 7 p.m. 



RICHARDS' SHOW ROOMS, 



3 Beauchamp Place, Broinpton RoaiJ, South Kensington, 

 London, S.W. 



MICROSCOPICAL PETROGRAPHY. 



Gentlemen interesied in the above study arc invited to send to 



JAMES R. QREOORY & CO., 



I Kelso Place, Kensington Court, London, W., 



for a Pro.spectus of 



THE TWENTIETH CENTURY ATLAS OF 



MICROSCOPICAL PETROGRAPHY, 



now being issued in Twelve Monthly Parts, each Part containing Four Fine 

 Half- Tone Plates, and also Four actual Rock Sections. 



Subscription in advance, either Monthly, 7/-; Quarterly, 21/-; 

 or for the whole Series of 12 Monthly Parts & 48 Sections, £4 4s. 



LIVING SPECIMENS FOR 

 THE MICROSCOPE. 



Volvox, Spirogyra, Desmids, Diatoms, Amoeba, Arceila, Actinosphaerium, 

 Vorticella, Stentor, Hydra, Floscularia, Stephanoceros, Melicerta, and many 

 other specimens of Pond Life. Price is, per Tube, Post Free. Helix 

 pomatia, Astacus, Amphioxus, Rana, Anodon, >ic., for Dissection purposes. 



THOMAS BOLTON, 



25 BALSALL HEATH ROAD, BIRMINGHAM. 



MARINE BIOLOGICAL ASSOCIATION 



OF THE UNITED KINGDOM. 



THE LABORATORY, PLYMOUTH. 



The following animals can always be supplied, either living 

 or preserved by the best methods : — 



Sycon; Clava, Obelia, Sertularia ; Actinia, Tealia, CaryophylUa, Aicy- 

 onium ; Hormipbora (preserved) ; Leptoplana ; Lineus, Ampbiporus, 

 Nereis, Aphrodite, Arenicola, Lanice, Terebella : Lepas, Balanns. 

 Gammarus, LigiaMysis, Nebalia, Carcinus; Patella, Buccinnm, Elodone, 

 Pectens Bugula, Crisia, Pedicellina, Holotburia, Asterias, Echinus, 

 Ascidia, Salpa (preserved), Scyllium, Rala, &e., &c. 



For prices and more detailed lists apply to 



Biological Laboratory, Plymouth. 



THE DIRECTOR. 



PHCENIX 



ASSURANCE COMPANY. LIMITED. 



FIRE OFFICE. 



19 LOMBARD ST., E.G., and 57 CHARING CROSS, S.W. 



Established 1782. 



Moderate Rates. Absolute Security. Blectrlc 



LlKbtlng Rules Supplied. Liberal Loss Settlements. 



Prompt Payment of Claims. 



LOSSES PAID OVER ie28, 000,000. 



BIRKBEGK BANK 



ESTABLISHED 1851. 

 Current Accounts. 2% Interest allowed on minimum 



monthly balances when not drawn below j^ioo. 

 Deposits. 2i°o Interest allowed on Deposit Accounts. 

 Advances made. Stocks and Shares bought and sold 

 Apply C. F. Ravenscroft, Secretary, 



Southampton Buildings, High Holborn, W.C. 



THE NEW COLLECTION OF 



336 SPECIMENS AND SLIDES OF ROCKS, 



accoFding to H. ROSENBUSCH : " Elemente der 

 Gesteinslehre, 2d ed. 1901." 



Accompanied by a text-book; ^^ Practical Petrography " giving a short 

 description of the pol<iri2ing microscope and its application, and also of the 

 macroscopical and microscopical features of every specimen of this collec- 

 tion, by Professor Dr. K. Busz of the University of Miinster. This 

 collection is intended for the practical use of students, and contains typical 

 representatives of all important types of rocks; it is composed of 277 

 massive rocks (94 deep-seated rocks, 50 dike rocks, r33 volcanic rocks), 

 28 sedimentary, and 31 crystalline schists. Out of it two smaller collections 

 of 250 and 165 specimens have been selected. The prices are as follows :— 

 Collection I. 336 Specimens of Rocks ... 380 Marks. 



la. 336 Slides 420 



,, II. 250 Specimens of Rocks ... 270 



Ila. 250 Slides 310 



,. III. 165 Specimens of Rocks 170 ,, 



Ilia. 165 Slides 205 



COLtEGTIONS OF MINERALS, FOSSILS, METEORITES, 

 PURCHASED FOR CASH OR EXCHANGED. 



The fifth edition of Catalogue No. 4, Petrograpliy, has just 

 been published (210 pages), and will be sent free ot charge on 

 application. 



Dr. F. KRANTZ, 



RHENISn MINERAL OFFICE, BONN-ON-RHINE, GERMANY. 



ESTABLISHED 1S33. 



WATKINS & DONCASTER, 



Naturalists and Manufacturers of 



CABINETS AND APPARATUS 



SPECIAL SHOW-ROOM FOR CABINETS. 



N,B.— For E.xcellence and Superiority of Cabinets and Appar.itus, refer- 

 ences .ire permitteil to distingulsli.;d p.ilroiis, .Museums, Colleges, &c. 



A LARUE STOCK OF INSECT5. B1«0S' EOQS AND SKINS. 



SPECIALITY.-Objects for Nature Study, Drawing 



Classes, &c. 



Birds, Mammals. &c.. Preserved and Mounted by First-class 



Workmen true to Nature. 



AH Books and Publications on Natural History supplied. 



36 STRAND, LONDON, W.C. 



(Five Doors from Charing Cross.) 

 £«- Xrir Caliilogtie (lO'i pp.) just issued, pust tire. 



ROCKS, MINERALS, FOSSILS. 



For Collectors, Students, Technical Schools, Colleges, &e. 



COLLECTIONS IN POLISHED DEAL BOXES. 



25 Specimens, 5/6; 50 do., 10/6; 100 do., 21/-; 200 do., 42/- 



20 Coal Measure Rocks and FnssiU. 12/6; do., larger, 15/-. 



Adapted for the Board of Education Examinations In 



Geology, Physiography, and Mineralogy. 



A iargi ttock 0/ Mintrals, Roiks, Fossils anti Microscopic Objicts for 



stlection S/'icifttHS stnt on apf'roTal 



Cabinets, Geologists' Hammers, Chisels, Card Trays, Glass-capped 



Boxes Models of Crystals, &c., &c. 



NEW CATALOGUE POST FREE 



THOMAS D. RUSSELL, 78 Newgale :ii., London, E.G. 



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